Taxa distribution and RAPD markers indicate different origin and regional differentiation of hybrids in the invasive Fallopia complex in central-western Europe
[en] Interspecific hybridization can be a driving force for evolutionary processes during plant invasions, by increasing genetic variation and creating novel gene combinations, thereby promoting genetic differentiation among populations of invasive species in the introduced range. We examined regional genetic structure in the invasive Fallopia complex, consisting of F. japonica var. japonica, F. sachalinensis and their hybrid F. × bohemica, in seven regions in Germany and Switzerland using RAPD analysis and flow cytometry. All individuals identified as F. japonica var. japonica had the same RAPD phenotype, while F. sachalinensis (11 RAPD phenotypes for 11 sampled individuals) and F. × bohemica (24 RAPD phenotypes for 32 sampled individuals) showed high genotypic diversity. Bayesian cluster analysis revealed three distinct genetic clusters. The majority of F. × bohemica individuals were assigned to a unique genetic cluster that differed from those of the parental species, while the other F. × bohemica individuals had different degrees of admixture to the three genetic clusters. At the regional scale, the occurrence of male-fertile F. sachalinensis coincided with the distribution of F. × bohemica plants showing a high percentage of assignment to both parental species, suggesting that they originated from hybridization between the parental species. In contrast, in regions where male-fertile F. sachalinensis were absent, F. × bohemica belonged to the non-admixed genetic group, indicating multiple introductions of hybrids or sexual reproduction among hybrids. We also found regional differentiation in the gene pool of F. × bohemica, with individuals within the same region more similar to each other than to individuals from different regions.
Taxa distribution and RAPD markers indicate different origin and regional differentiation of hybrids in the invasive Fallopia complex in central-western Europe
Abbott RJ. Plant invasions, interspecific hybridisation and the evolution of new plant taxa. Tree 1992, 7:401-405.
Ainouche ML, Baumel A, Salmon A, Yannic G. Hybridization, polyploidy and speciation in Spartina (Poaceae). New Phytologist 2003, 161:165-172.
Bailey JP. Japanese Knotweed at home and abroad. Plant Invasions: Ecological Threats and Management Solutions 2003, 183-196. Child LEBrock JHBrundu G. In, Eds, Backhuys Publishers, Leiden
Bailey JP, Conolly AP. Prize-winners to pariahs - a history of Japanese Knotweed s. l. (Polygonaceae) in the British Isles. Watsonia 2000, 23:93-110.
Bailey JP, Stace CA. Chromosome number, morphology, pairing, and DNA values of species and hybrids in the genus Fallopia. Plant Systematics and Evolution 1992, 180:29-52.
Bailey JP, Wisskirchen R. The distribution and origins of Fallopia × bohemica (Polygonaceae) in Europe. Nordic Journal of Botany 2006, 24:173-200.
Bailey JP, Child LE, Wade M. Assessment of the genetic variation and spread of British populations of Fallopia japonica and its hybrid Fallopia × bohemica. Plant Invasions - General Aspects and Special Problems 1995, 141-150. Pysek P, Prach K, Rejmanek MWade M. In, Eds, SPB Academic Publishing, Amsterdam
Bailey JP, Child LE, Conolly AP. A survey of the distribution of Fallopia × bohemica (Chrtek & Chrtkova) J. Bailey (Polygonaceae) in the British Isles. Watsonia 1996, 21:187-198.
Bailey JP, Bimova K, Mandak B. The potential role of polyploidy and hybridisation in the further evolution of highly invasive Fallopia taxa in Europe. Ecological Research 2007, 22:920-928.
Callaway RM, Maron J. What have exotic plant invasions taught us over the past 20 years? Trends in Ecology and Evolution 2006, 21:369-374.
Dlugosch KM, Parker IM. Founding events in species invasions: genetic variation, adaptive evolution, and the role of multiple introductions. Molecular Ecology 2008, 17:431-449.
Doyle JJ, Doyle JL. Isolation of plant DNA from fresh tissue. Focus 1990, 12:13-15.
Ellstrand NC, Roose ML. Patterns of genotypic diversity in clonal plant species. American Journal of Botany 1987, 74:123-131.
Ellstrand NC, Schierenbeck KA. Hybridization as a stimulus for the evolution of invasiveness in plants? PNAS (Colloquium) 2000, 97:7043-7050.
Evanno G, Regnaut S, Goudet J. Detecting the number of clusters of individuals using the software structure; a simulation study. Molecular Ecology 2005, 14:2611-2620.
Forman J, Kesseli RV. Sexual reproduction in the invasive species Fallopia japonica (Polygonaceae). American Journal of Botany 2003, 90:586-592.
Friedmann JM, Roelle JE, Gaskin JF, Pepper AE, Manhart JR. Latitudinal variation in cold hardiness in introduced Tamarix and native Populus. Evolutionary Applications 2008, 1:598-607.
Gabrielsen TM, Brochmann C. Sex after all: high levels of diversity detected in the arctic clonal plant Saxifraga cernua using RAPD markers. Molecular Ecology 1998, 7:1701-1708.
Galbraith DW, Harkins KR, Maddox JM, Ayres NM, Sharma DP, Firoozabadi E. Rapid flow cytometry analysis of the cell cycle in plant tissue. Science 1983, 220:1049-1051.
Fallopia japonica. 2005, http://www.issg.org/database/species/ecology.asp?si=91&fr=1&sts=&lang=EN, GISD, Available at (accessed 20 August 2008)
Grimsby JL, Tsirelson D, Gammon M, Kesseli R. Genetic diversity and clonal vs. sexual reproduction in Fallopia spp. (Polygonaceae). American Journal of Botany 2007, 94:957-964.
Hänfling B, Kollmann J. An evolutionary perspective of biological invasions. Trends in Ecology and Evolution 2002, 17:545-546.
Hardy OJ. Estimation of pairwise relatedness between individuals and characterization of isolation-by-distance processes using dominant genetic markers. Molecular Ecology 2003, 12:1577-1588.
Hardy OJ, Vekemans X. SPAGeDi: a versatile computer program to analyse spatial genetic structure at the individual or population levels. Molecular Ecology Notes 2002, 2:618-620.
Hollingsworth ML. Evidence for massive clonal growth in the invasive weed Fallopia japonica. Botanical Journal of the Linnean Society 2000, 133:463-472.
Hollingsworth ML, Hollingsworth PM, Jenkins GI, Bailey JP, Ferris C. The use of molecular markers to study patterns of genotypic diversity in some invasive alien Fallopia spp. (Polygonaceae). Molecular Ecology 1998, 7:1681-1691.
Lambrinos JG. How interactions between ecology and evolution influence contemporary invasion dynamics. Ecology 2004, 85:2061-2070.
Lee CE. Evolutionary genetics of invasive species. Trends in Ecology and Evolution 2002, 17:386-391.
Mandak B, Pysek P, Lysak M, Suda J, Krahulcova A, Bimova K. Variation in DNA-ploidy levels of Reynoutria taxa in the Czech Republic. Annals of Botany 2003, 92:265-272.
Mandak B, Bimova K, Pysek P, Stepanek J, Plackova I. Isoenzyme diversity in Reynoutria (Polygonaceae) taxa: escape from sterility by hybridization. Plant Systematics and Evolution 2005, 253:219-230.
Mooney HA, Hobbs RJ. Invasive Species in a Changing World 2000, Island Press, Washington, D.C
Ozkan H, Levy AA, Feldman M. Allopolyploidy-induced rapid genome evolution in the wheat (Aegilops-Triticum) group. The Plant Cell 2001, 13:1735-1747.
Pashley CH, Bailey JP, Ferris C. Further evidence of the role of Dolgellau, Wales, in the production and dispersal of Japanese knotweed s.l. Plant Invasions: Ecological Threats and Management Solutions 2003, 197-211. Child L, Brock JH, Brundu G. In, Blackhuys Publisher, Leiden
Prentis PJ, Wilson JRU, Dormontt EE, Richardson DM, Lowe AJ. Adaptive evolution in invasive species. Trends in Plant Science 2008, 13:288-294.
Pritchard JK, Wen W. Documentation for structure Software 2004, The University of Chicago Press, Chicago, IL
Pritchard JK, Stephens M, Donnelly P. Inference of population structure using multilocus genotype data. Genetics 2000, 155:945-959.
Rieseberg L, Kim S-C, Randell R, Whitney K, Gross B, Lexer C, Clay K. Hybridization and the colonization of novel habitats by annual sunflowers. Genetica 2007, 129:149-165.
Sakai AK, Allendorf FW, Holt JS, Lodge DM, Molofsky J, With KA, Baughman S, Cabin RJ, Cohen JE, Ellstrand NC, McCauley DE, O'Neil P, Parker IM, Thompson JD, Weller SG. The population biology of invasive species. Annual Review of Ecology and Systematics 2001, 32:305-332.
Salmon A, Ainouche ML, Wendel JF. Genetic and epigenetic consequences of recent hybridization and polyploidy in Spartina (Poaceae). Molecular Ecology 2005, 14:1163-1175.
Tiébré M-S, Bizoux J-P, Hardy OJ, Bailey JP, Mahy G. Hybridization and morphogenetic variation in the invasive alien Fallopia (Polygonaceae) complex in Belgium. American Journal of Botany 2007a, 94:1900-1910.
Tiébré M-S, Vanderhoeven S, Saad L, Mahy G. Hybridization and sexual reproduction in the invasive alien Fallopia (Polygonaceae) complex in Belgium. Annals of Botany 2007b, 99:193-203.
Vilá M, Weber E, D'Antonio CM. Conservation implications of invasion by plant hybridization. Biological Invasions 2000, 2:207-217.
Weber E. Invasive Plants in the World: A Reference Guide to Environmental Weeds 2003, CABI-Publishing, London
